Campagnolo 2015 Super Record UT 34/50 Crankset

If maximum performance at minimal weight is what you seek, then look no further than the latest lineup of Super Record components from Campagnolo. Designed around the quest for utmost efficiency, this groupset is at the pinnacle of what road bikes should be outfitted with. A tremendous amount of research, development, and testing has gone forth to bring you this "maximum evolutionary and technological expression of a mechanical drivetrain", as Campy themselves put it.

Crankset

Double standardized bolt circle diameter on all combinations. Meaning you can swap chainring combinations without having to get an entirely new crankset 
Titanium axle and reverse thread titanium fixing bolt 
Hollow cranks and spider arms with Ultra-Hollow™ Technology 
Ultra-Torque™ axle 
New chainrings 
Differentiated number of pins depending on the chainring combination 
CULT™ Technology (Ceramic Ultimate Level Technology)
X.P.S.S.™ (Extreme Performance Shifting System) 
Ultra - Torque™